and their relation to existing Animals. 1 23 



morpholithic, which have the appearance of a secondary forma- 

 tion, differ in some respects from the chalk Morpholithes (Kreide- 

 Morpholitheri), being sometimes stelliform, sometimes elliptical 

 with a nucleus. 



The rocks in general containing these forms, which are some- 

 times scarcely discernible, at other times little changed, and 

 occasionally surprisingly well preserved, are partly Tripoli, very 

 friable and whitish in appearance, partly compact calcareous 

 sandstone, and become marly by a combination with a consider- 

 able quantity of calcareous earth. 



In some localities the strata of marl contain semi-opal, and oc- 

 casionally veins of a carboniferous appearance. Burnthill, which 

 has been considered by some of the inhabitants to be of volcanic 

 origin, does not show any traces of having been on fire on the 

 summit ; the rocks have received the blackish appearance from 

 the admixture of bitumen, which they lose when subjected to fire. 

 They contain Polycystina in good preservation*. 



The semi- opal is a very remarkable character of the Barbados 

 formation, which has hitherto not occurred in calcareous marls, 

 while on the other hand flints, which are so numerous in the Eu- 

 ropean chalk formation, are entirely wanting in Barbados. Semi- 

 opal occurs sometimes in Europe in the tertiary biolithic Tripoli. 



Another remarkable peculiarity of the Barbados marls is the 

 large admixture of pumice, which would almost authorize the de- 

 nomination of a volcanic tufa. One of the geological specimens, 

 from Skeete's Bay (No. 58), consists of a pure volcanic tufa. 

 Professor Ehrenberg does not recollect having previously met 

 with a similar combination of volcanic dust or ashes/ chalk and 

 marl ; and it is his opinion " that these rocks, which consist of vol- 

 canic ashes and organic remains, formerly constituted a submarine 

 bottom which was subsequently raised, and hence these rocks belong 

 to a much older period than the coralline rocks which rest upon the 

 former and constitute the largest portion of the superficial area 

 of the island" The whole formation of the island possesses a 

 uniformity of character which is only modified by different com- 

 binations, changes and transformations. 



The minute forms of organic life in the rocks of Barbados, as 

 far as investigated by Professor Ehrenberg in February 1847, 

 consist of the following groups : — 



Species. 



Polycystina 282 



Polygastrica 18 



Phytolitharia 27 



Geolithia 27 



Polythalamia 7 



30 1 

 Of these more than three hundred are new forms. 



* There is a tradition in existence that this hill was burning for the space 

 of five years, the bitumen having been set accidentally on fire. 



9* 



